Added a note about VirtualEnv and use of sudo in the README for installing the Python Flask dependencies.
Added a note about VirtualEnv and use of sudo in the README for installing
the Python Flask dependencies.

apiri/openxc-vehicle-simulator,NitishKSharma/openxc-vehicle-simulator,openxc/openxc-vehicle-simulator,iamthebest77/openx,NitishKSharma/openxc-vehicle-simulator,openxc/openxc-vehicle-simulator,worldline-spain/openxc-vehicle-simulator,iamthebest77/openx,openxc/openxc-vehicle-simulator,dhootha/openxc-vehicle-simulator,apiri/openxc-vehicle-simulator,dhootha/openxc-vehicle-simulator,iamthebest77/openx,worldline-spain/openxc-vehicle-simulator,apiri/openxc-vehicle-simulator,NitishKSharma/openxc-vehicle-simulator,worldline-spain/openxc-vehicle-simulator,dhootha/openxc-vehicle-simulator